Engine starter



ENGINE STARTER Filed Oct. 3l, 1931 /NVENTOR Patented Feb. 14, 1933 UNITED STATESw PATENT OFFICE MAURICE P. WHITNEY, F ELMIRA, NEW YORK, ASSIGNOR TO ECLIPSE MACHINE COM- PANY, OF ELMIRA, NEW YORK, A CORPORATION OF NEW YORK i ENGINE YS'IARTER Application led October 31, 1931. Serial No. 572,265.

This invention relates to an engine starter and more particularly to a rebound check and anti-drift device for starter drives.

In starter drives of the type in which a driving pinion is automatically traversed into and out of mesh with a member such as a flywheel gear of an engine to be started, some difficulty is occasionally encountered in preventing the pinion from drifting into engagement with the engine member while the engine is running due to vibration or other causes, and it also not infrequently occurs in some installations that the pinion when thrown out of mesh with the engine member as the engine starts will rebound from its idle position and kstrike theside of the rotating engine member. Both of these conditions are undesirable, since they are productive of unnecessary wear and noise.

It is an object of the present invention to provide a starter drive embodying a novel device for yieldably resisting drifting of a starting pinion into undesired engagement with an engine member and for positively preventing the pinion from bounding back toward the engine member when it is thrown out of engagement therewith.

Another object of the invention is to pro-V vide such a device which does not interfere with the automatic traversal of the pinion into mesh with the engine member when the starting mechanism is actuated.

A further object is to provide such a device which is readily adaptable without undue expense to various existing types of drive.

Further objects and advantages will be apparent to those skilled in this art from the following description taken in connection with the accompanying drawing in which Fig. 1 is a side elevation of a starter drive embodying one preferred form of the invention;

Fig. 2 is a cross section taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a view similar toFig. 1 of a second embodiment of th-e invention;

Fig. 4 is a cross section taken substantially on the line 4 4 of Fig. 3;

Fig. 5 is a detail in section substantially on the line 5-5 of Fig. 4 showing the 'antidrift device in operative position;

Fig. 6 is a similar detail showing therebound check in operative position;

Fig. 7 is an enlarged sectional detail showing the shoulder formed on the screw shaft for cooperating with the retaining means on the pinion;

Fig. 8 is a side elevation of another embodiment of the invention;

Fig. 9 is a cross section taken substantially on the line 9-9 of Fig. 8. v l

Referring first to Figs. 1 and 2 of the drawing, there is illustrated a shaft 1 which may be the extended'armature shaft of a starting motor (not shown) and having a driving head 2 fixed thereon as by means of a key 3 and stud4. kThe stud 4 serves as an anchorage for a driving spring. 5 the other end of which is anchored as by means of a stud 6 on the driving head 7 formed on the'end of a power member in the form of a screw shaft 8 which is freely journaled on the shaft 1. A driving member in the form of a pinion 9 is threaded on the screw shaft 8, and is adapted to be traversed into and out of mesh with an engine member vsuch as a flywheel gear 11, the driving position of the pinion being defined by a suitable stop 12` on the screw shaft 8, and the idle position of the pinion being defined by shoulders 13 formed on the ends of the shaft threads. Y

According to the present invention, means are provided for yieldably resisting traversal of the pinion 9 away from its idle position when the screw shaft 8 is not being rotated, and for positively preventing such traversal when the parts are rotating rapidly at the time the pinion is thrown out of mesh with the engine member 11. For this purpose, a shoulder 14 (Figs. 5 and 6) is formed on the screw shaft 8, and a retaining member. 15 (Fig. 2) in the form of a bell crank lever isv pivoted at 16 on a flange 17 of the pinion in suchV positionthat either of the arms 18 or 19 of the retaining member may move into engagement with the screw shaft and bear against the shoulderk 14 thereon. The arm 18 of the retaining member 15 is rounded on its inner edge as at 21 (Fig. 5) and is yieldingly maintained in engagement with the screw shaft when the parts are stationary by suitable means such as a spring 22 which is mounted on the pivot pin 16 in position to Serve as a retaining means for the lever 15, and is `bent at right angles atV its outer end as indicated at 23 (Fig. 3) in order to engage any one of the openings 24 in the arm. 18 for adjustably urging said arm into engagement with the screw shaft. The arm 19T is rectangular in'cross section forming a radial shoulder adapted to engage the shoulder 14 of the screw shaft and thus positively prevent relative longitudinal motion between the pinion and screw shaft. rlhe arm 18 is weighted sufficiently tooverbalance the armV 19` and' the arm' 19"is performedentirely by theengagement ofthe side lof said'arm against the shoulder'14 ofthe screw shaft 8, as illustratedinFig.-6. Fig. 7 illustrates the-shouli der14- on an enlarged'sca-le, showing-a bevl' eled-surface'26 `arranged to engage the roundediedge-21offthe arm 18-and aradial surface 27? adapted to engage the square side of. they lockinglarm'19: The remainingpartsof the driveare the same as those illustrated in Figsf 1 andi2'and'are` similarlyfnumbered;

Figs. 8" and 9illustrate an en'ibodimentl off the-invention in-which Ashoulderscorresponding `to :the'beveled surface l26 and radial surface 27 of Fig. 7 l' are -formedin'axially separated planeson the screw shaft, and the retaininglmeans cooperatingtherewith are Vformed in separate axialL planes. As there illustrated, abeveled shoulderA 28f`isf'ormedon the `screw shaft in position to be engaged by any arm291of a-retaining member l31 pivoted at32 on the pinion 9;fanda radial shoulder 33is formedon the screw shaft iii-position to be engaged by. a locking 'arm 34 of the-retainingmember'l which arm `is offset-axially 'f from the arm 29 as clearly seen yin Fig. 8:

The' arm 29 is` normally urged` into engagement with the screwshaft by suitable' means such as aspri'ng 35and is weighted so as to move outwardly under the action Vofl centrifugal force, thus bringing'the' armz34 into engagement-with the screw shaft whenthe pinionis rapidly rotating. The shoulder 33' onthe screw shaftsis preferably bevelledon itsy forward side as indicated at 36'so as to allow. theI arm`34to pass over the shoulder when the pinion is being returned to its idle position. The remaining parts of the drive illustrated in Figs. 8 and 9 are also similar to those shown in Figs. 1 and 2 and are similarly numbered.

In-operation, the pinion 9 is normally retained in its-idle positiononthe screw shaft 8 bythe engagement of the arm 18 (Figs. 1 and 2)4 or 29 (Figs. 8. and 9) which is yieldably heldlagainst the screw shaft' in engagement with the bevelled shoulder thereon. Vhen the shaft 1 is operated, rotation is transmitted through the drive spring 5 to the screw shaft:` 8in=the direction of the arrow in Fig. 1. Pinion 9, due to its inertia is not immediately set-into rotation-and-is therefore traversed' along the threads 8f into-engagement with the engine member, the anti-drift member 18 or'29 being cammed-outby the inclinedzshoulders on the screw shaft. When the'engine starts thefpinion israpidly accelera-tedsofa's to overrun the screw shaft and is therefore thrown back to its idle position on saidshaft: vDueto therapid rotation of= the pinion a-t1thisftimethe locking-arm 19 orl 34 thereof is forcibly urged-against the screw shaftby the action of-centrifugal `force whereby said arm-is-causedto lodge back ofthe-radialshoulder on the screw shaft and positively prevent rebounding of the'pinion toward the engine member. Vhen-the Sta-rting motor'is' deenergized, the parts of'the drive are rapidly decelerated, thusmaintainingthe pinion 9lin its idle position until rotation ceases, whereupon theV anti-drift arm 18for 29 rengages the screw shaft andfyieldably'resists traversal of the pinion until the starting mechanism isfagain actuated.

Although certain embodiments ofl the invention havebeen shown and described in detail, itwill be understood; that various changes may be made in the proportions-and arrangements of the parts and certafin'elements usedA without other elements ifI so desired withouty departing from the spirit of the invention as denedin the Claims appended hereto.

That is claimedis 1. A starter drive comprising a power member, af driving memberl mounted thereon for longitudinal movement into and out ofengagementV witha member of anengine to be started, and'for rotary movement thereofand therewith, detent mea-ns for yieldably resisting'traversall of the driving member away from idle positiony and'loclring means operable'by centrifugal force to positively prevent such traversal.

2. A starter drive comprising a-y power member, a drivingniember mounted thereon for-longitudinal movement into'and out of engagement witha member of an engine to be started, and for' rotary movement thereof and therewith, said members having detent means to resist traversal ofthe driving member from idle position, said members also having locking means adapted to cooperate to positively prevent such traversal, and means normally maintaining said detent means in cooperative relation and said locking means out of cooperative relation, but yieldable under tie influence of centrifugal force to allow the cooperation of said locking means.

S. A starter drive comprising a screw shaft, driving pinion threaded thereon for automatic traversal into and out of engagement with a member of an engine to be started, one of said members being shouldered, the other member having a pair of elements adapted to cooperate therewith, one yieldingly and the other positively, to retain the driving pinion in idle position, means for normally retaining` the yielding element in operative position, and centrifugal means for moving the positive element into operative position.

4. A starter drive comprising a screw shaft, a driving pinion threaded thereon for automatic traversal into and out of engagement with a member of an engine to be started, one of said members having an inclined shoulder and a radial shoulder, the other member having a pair of elements formed as the arms of a lever pivoted thereto, one arm adapted to cooperate with the inclined shoulder on the other member to yieldingly retain the pinion in idle position, and the other arm being adapted to cooperate with the radial shoulder to positively lock the pinion on the shaft, said lever being movable by centrifugal force to bring the locking arm into operation.

5. A starter drive comprising a screw shaft, a driving pinion threaded thereon for automatic traversal into and outof engagement with a member of an engine to be started, said shaft being shouldered adjacent the outer position of the pinion, said pinion having an arm pivoted thereto and adapted to have an inclined sliding engagement with the shouldered portion of the shaft, said pinion having a second arm pivoted thereto, adapted to make positive latching engagement therewith, yielding means for moving the first arm into engagement with the shaft and the second arm out of such engagement, and centrifugal means for reversing the position of the arms.

6. A starter drive comprising a screw shaft, a driving pinion threaded thereon for automatic traversal into and out of engagement with a. member of an engine to be started, said shaft being shouldered adjacent the outer position of the pinion, said pinion having a latch in the form of a bell crank lever pivoted thereto, one arm thereof being rounded to make an inclined frictional engagement with a shoulder on the shaft, and the other arm having a radial surface to engage positively a radial shoulder on the shaft, a spring for s vinging the lever to move the rounded arm into engagement with the shaft, said rounded arm being weighted whereby cen- MAURICE P. WHITNEY. 

